Latest Omega-3 Prostate Cancer Study – Don’t Believe All You Read
Omega-3 and prostate cancer are making headlines after the latest study. There is good and bad about getting your health information off the Internet. The good is that you have all the latest studies at your fingertips. And the bad is that you have all the latest studies at your fingertips. The media loves to jump on the latest story that goes against all the other evidence. How does this relate to omega-3 fatty acids from fish oil and your prostate you ask? Well there are countless studies on the benefits of taking omega-3 fatty acids for prostate health, but then one recent study on omega-3 and prostate cancer was published stating the opposite, that omega-3 fatty acids can cause prostate cancer. That leaves people like us who don’t know whether to keep heading up stream or turn around and forget everything we have ever known about these healthy oils.
What Is Omega-3?
Omega-3 fatty acids are considered essential because they are not made by the body and must be consumed through food or supplements. Common sources are fish oil and flaxseed oil. Omega-3 fatty acids are a type of polyunsaturated fat that has many health benefits in the body including lowering cholesterol and triglycerides, being good for blood pressure and cardiovascular health, helping the body with responding to insulin, and by preventing cancer cell growth including prostate cancer.
What Are the Studies on Omega-3 Preventing Prostate Cancer?
Researchers conducted a study at UC San Francisco that was published in 2009 on omega-3 and prostate cancer. They studied 466 men with an aggressive form of prostate cancer and 478 healthy men. They screened the men for a gene known to increase risk of prostate cancer and had them men fill out questionnaires about diet.
After compiling the data, researchers saw that men who ate dark fatty fish like salmon at least once per week had a 63% reduced risk of developing prostate cancer. Men who consumed little to no fish and had the gene variation were 5 times more likely to develop advanced prostate cancer. The researchers concluded that omega-3 might decrease inflammation in the prostate and the progression of cancer by having an effect on the gene.
Cancer Prostate in Sweden
A large Swedish study also looked at men who had this same gene and fish consumption. Researchers found that the risk of prostate cancer was 43% lower in men who consumed salmon and similar fish more than one time per week when compared with men who never ate fatty fish.
Researchers conducted a large Physician’s Health Study at Harvard School of Public Health of over 20,000 men. They found that of the men diagnosed with prostate cancer, the men who ate fish at least 5 times per week had a 48% lower risk of dying from prostate cancer.
What About the Latest Study?
Keep in mind that this is one study, and it may not be the best study. It is a retrospective study as described by Dr. Geo, which means it looks back over time at a different trial and it does not show cause and effect. This study was conducted by Theodore Brasky and his team. The abstract can be found here.
The researchers looked at specimens from the SELECT trial. These findings indicate that high concentrations of EPA, DPA, DHA (which are anti-inflammatory fatty acids that come from fatty acids and fish oil supplements) are connected to a 71% increase in the risk for high-grade prostate cancer. Additionally, the study found a 44% increase in the risk of low-grade prostate cancer, and a 43% increase in risk for all kinds of prostate cancers. But what the researchers did not account for is the known risk factors of prostate cancer:
- PSA level
- DRE (digital rectal exam)
- Body Mass Index (BMI)
These known risk factors were not considerations in the study, which could heavily affect the findings. Also, the study did not say when the men started taking fish oils, before or after they were diagnosed with prostate cancer.
An interesting aspect of this study is that is found that omega-6 fatty acids were associated with a lower risk of prostate cancer, which is in conflict with most other studies. Most other research has found excessive omega-6 fatty acids to contribute to the risk of prostate cancer. Also interesting is that the study group published a paper in 2011 stating that unhealthy trans fatty acids (found in margarine and known to increase risk of heart disease) were associated with decreasing the risk of aggressive prostate cancer. These researchers are going against mountains of well-researched evidence against trans fat, omega-6 and omega-3.
Other Studies About Prostate Health in the Media
This is a common phenomenon when a contradictory study hits the media. It happened in 2012 with saw palmetto, when Complementary and Alternative Medicine for Urological symptoms (CAMUS) trial studied saw palmetto for urinary symptoms from BPH and its effect on PSA. Saw palmetto works very well when combined with other herbal therapies such as stinging nettle and quercetin, but these studies did not combine saw palmetto with these other herbal therapies, and that is why they did not get the same results. You can read about saw palmetto and other reputable studies involving its benefits for prostate health here.
The same thing happened with SELECT trial regarding vitamin E in 2011. Vitamin E comes in eight forms, but only some of the forms, such as gamma tocopherol, are shown to help prevent prostate cancer. Previous research had found that another form of vitamin E, alpha-tocopherol, robs cells of cancer-fighting gamma-tocopherol. The SELECT study only studied one form of vitamin E, alpha-tocopherol. Authors of the study published in JAMA that healthy men who had an average risk of prostate cancer took 400 IU of vitamin E each day and showed a 17% increased risk of prostate cancer compared to men who took a placebo. Without understanding the limitations of the study or the different types of vitamin E, the media took off with the story that vitamin E causes prostate cancer, when really only one form had been studied and it was not the form that many other studies had found to be beneficial.
So Now What?
When faced with opposing evidence, readers must use common sense and read between the lines. Don’t let one study form your opinion. Look for other sources to support a study before forming an opinion and find out specifically what form of a treatment was studied and other factor that could affect outcome. There are flaws in many studies. Look for results that are supported by multiple studies in multiple setting that have plenty of evidence to back them up. Look toward prospective studies that show cause and effect. There are many prospective studies that show the benefits of taking omega-3 fatty acids to lower risk of prostate cancer. You want to use products that say they are purified fish oils.
Consider the mountain of respectable evidence before jumping onto an island of contrary opinion. Talk to your doctor before starting or stopping a supplement or making a major dietary change based on the latest headlines. Ask questions and weigh the existing evidence to make smart decisions, especially in the case of omega-3 and prostate cancer. Unfortunately, most, if not all medical doctors have very little training in nutrition and supplements and base their advice on the latest “headlines” so be informed and educated before discontinuing what may be a vital health benefit such as Omega-3.
Listen to this excellent interview by Michael Savage, PH.D in epidemiology and nutrition and Anthony Victor D’Amico, MD, PH.D who has a doctorate from M.I.T on the Prostate Cancer and Omega 3 Study.
Click here to listen to the interview.
Brasky, T. Plasma Phospholipid Fatty Acids and Prostate Cancer Risk in the SELECT Trial. Journal of the National Cancer Institute.
Chavarro J. E. et al. A 22-y prospective study of fish intake in relation to prostate cancer incidence and mortality. Am J Clin Nutr 2008 Nov; 88(5): 1297-303.
Fradet, V., et al. Dietary omega-3 fatty acids, cycloocygenase-2 genetic variation, and aggressive prostate cancer risk. Clinical Cancer Research 2009; 15:2559.
Hedelin M et al. Association of frequent consumption of fatty fish with prostate cancer risk is modified by COX-2 polymorphism. Intl J Cancer 2007 Jan 15; 120(2): 398-405. omega-3 and prostate cancer